Template:POTD/2014-06-06
A male head louse, an obligate ectoparasitic insect which spends its entire life on the human scalp and feeds exclusively on human blood. It is one of three louse species which infects humans, along with the body louse and the crab louse. Head lice infestation is widely endemic, especially in children, and treatment of such infestations is not 100% effective; the lice themselves, however, are not disease vectors, and it has been suggested that they are beneficial to the body.Photograph: Gilles San Martin